Viral infection of humans is a major health problem, and viral infection of domesticated animals is a major economic concern. Combating viral infection has proven to be highly effective in some cases like smallpox where the disease was essentially eradicated with the advent of smallpox vaccination. Although smallpox was essentially eradicated by about 1980, there is considerable justified fear of the emergence of a new epidemic of smallpox since there are existing stockpiles of the virus and bioterrorism has moved beyond the realm of possibility to reality. Other viral infections have been much more difficult to fight. Human immunodeficiency virus (HIV), hepatitis B and C, herpes simplex viruses (HSVs) and influenza are just a few prominent members of a list of viruses that pose significant health threats worldwide. Additionally, emerging viral infections continue to threaten the world with human epidemics, as is illustrated by the recent outbreak of severe acute respiratory syndrome (SARS), which has now been associated with coronavirus infection. Treatments currently available for many viral infections are often associated with adverse side effects. In addition, antiviral therapeutics directed towards specific viral gene products frequently have the effect of driving the selection of viruses to become resistant to such therapeutics, and viral strains resistant to current methods of treatment are an increasing problem. Accordingly, there is a clear and ever-present need for new antiviral treatments.